本文以自制的纳米TiO2为光催化剂,研究了光催化条件(溶液pH值、催化剂浓度及甲胺磷浓度)对甲胺磷在水中降解率的影响。结果表明:通过优化催化条件,可以大大提高甲胺磷的降解率。在甲胺磷浓度为20mg/L,反应液起始pH为10.00,催化剂用量为0.5g/L,光照时间为3h的条件下,甲胺磷的降解效率可达到71.8%。通过化学计算模拟了甲胺磷的分子构型,并结合离子色谱的检测结果初步探讨了甲胺磷光催化降解的反应机理。
Photocatalytic degradation technique based on the titania nanoparticles, which can mineralize the methamidophos into nontoxic inorganic constituents, is an environmentally friendly treatment method for the pesticide polluted water. By using home-made TiO2 nanoparticles as the photocatalyst, the relationships between photocatalytic reaction conditions (such as pH value, catalyst and methamidophos concentration) and photodegradation efficiency for methamidophos in a suspension system are investigated through the molybdenum blues photometric method. The experimental results show that 71. 8% methamidophos can be mineralized into inorganic substances under the optimal photocatalytic conditions (e. g. 20 mg/L methamidophos, 0.5 g/L nano-TiO2 suspension (pH 10.00), 3 h UV illumination). After simulation computation of the methamidophos molecule and ion chromatographic detection of the mineralization products, the reaction pathways are preliminarily proposed.